1. Technical Field
The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device in which one pixel includes a transmissive portion for performing a transmissive display and a reflective portion for performing a reflective display and two electrodes for controlling the alignment of liquid crystal molecules are disposed in one substrate.
2. Related Art
Liquid crystal panels of an FFS (Fringe Field Switching) type or an IPS (In-Plane Switching) type are known as a liquid crystal panel having a wide viewing angle. In such types, both a pixel electrode and a common electrode are disposed in an element substrate, and liquid crystal molecules are rotated by the control of an electric field generated between both electrodes, thereby controlling alignment of the liquid crystal molecules.
The liquid crystal panels are approximately classified into a transmissive type of making a display by the use of a backlight, a reflective type of making a display by the use of an external light, and a transflective type having both the transmissive and reflective structures in one pixel.
JP-A-2003-270627, JP-A-2004-198922, JP-A-2005-338256, and JP-A-2003-344837 are examples of the related art.
The known transflective liquid crystal panels of a TN type and an ECB type do not have sufficient contrast and have a narrow viewing angle. The transflective liquid crystal panels of a VA type have high contrast and an enlarged viewing angle, but have a problem in that colors are changed in viewing from an angle.
In contrast to these TN type or ECB type liquid crystal panels, the transflective liquid crystal panels of an FFS type or an IPS type have excellent viewing-angle characteristic and have significantly small color changes in viewing from an angle, which is a problem of the VA type. However, it is necessary to dispose a retardation film or a wave plate so as to allow a transmissive display and a reflective display to coexist, which causes a problem with a decrease in contrast. In addition, there is also a problem in that the liquid crystal display device gets thicker than the transmissive liquid crystal display device of an FFS type or an IPS type.